Pipe insulation



July 27, 1937. R. R. BLACK 2,088,400

PIPE INSULATION Filed April 20, 1935 2 Sheets-Sheet l ATTORNEY July 2?, 1937. R R, BLACK 2,088,400

PIPE INSULATION Filed April 20, 1955 2 Sheets-Sheet 2 7 2 K E ZZZ BY 0A 4- ATTORNEY Patented July 27, 1937 2,088,400

UNITED STATES PATENT OFFICE PIPE INSULATION Roe R. Black, Douglaston, N. Y., assignor to Reynolds Corporation, New York, N. Y., a corporation of Delaware Application April 20, 1935, Serial No. I7,372

6 Claims. (Cl. 154-45) This invention relates generally to insulating foil, and may be made of sheet aluminum, or, in pipe coverings formed of resilient, flexible sheet fact, may be made of any metal having the metal and particularly to such sheet metal pipe requisite flexibility, resiliency and reflective covering having integral therewith spacing and qualities.

connective means for successive units of the same. A particular advantage of my p pe Covering 5 Heretofore, while there have been a plurality in its preferred form, is that it tends to remain of pipe insulations, they have been subject to cerin fixed position upon a pipe due to opposing tain disadvantages. Some have been expensive forces set up between the resilient spacers and to manufacture, or inconvenient to ship; others the U-body of the covering itself. A further adhave been expensive and difficult to mount in vantage is that the all-metal covering does not 10 place upon a pipe, or have been bulky and ugly. absorb moisture; thus it can be used inside or Some pipe coverings have had low insulation outside of a building and for underground conefficiency, have required frequent painting, and duits. have rapidly deteriorated under practical work- My invention can readily be understood from ing conditions, particularly where exposed to the accompanying drawings which are set forth 15 dampness and water. Most of the more eflicient merely for the purposes of illustration and are insulations are ruined if it is found necessary to not to be deemed as limiting the scope of my remove them temporarily from any pipe upon invention. which they are mounted. In the drawings,

To overcome the above difficulties, I have de- F 1 is pelspective View Of a P covering 20 vised a simplified all-metal pipe covering formed unit embodying my invention, showing the same of thin gage, flexible and resilient sheet metal, flexed under tension into a generally tubular which is cheap and easy to manufacture and also form; cheap and easy to install on a pipe. Under prac- Fig. 2 is a perspective view of this unit shown tical working conditions it is long lived and may in Fig. 1 but shown without tension and. in its 25 be readily dismounted from its pipe Without innormal generally U-shape; jury. Such covering of sheet metal should have 3 s a Cross Section of a p p Covering a bright reflective surface. at least upon its inner formed of sheet metal having an aluminum foil side, such surface being obtained either by the coating upon both its inner and outer surfaces;

type of sheet metal which is employed or by some Fig. 4 is a longitudinal cross section showing 30 type of coating. The pipe covering is preferably two units of pipe covering connected together formed in a U-shape and this permits nesting so and mounted in place upon a pipe;

that various units of the covering may be easily 5 s a tra sver C oss Section on the line shipped. This is a decided advantage. Also of 4; because of the flexibility and resiliency of the Fig. 6 s a t ansv se cr ss ct n f a P p 35 metal when the U-shaped member is flexed into havi tW p pe coverin units mounted One Over a generally tubular shape around a pipe, the inthe other in order to obtain high insulation value;

herent resilience of the metal may be utilized by Fig. 7 is a longitudinal cross section of two some hooking means to hold the ends of the U pipe coverings mounted one above the other; together. In my preferred form I provide one Fig. 8 is afragmentary cross section of a modi- 40 crimped end on each unit of my pipe covering, fication of my invention showing a crimped end which crimped end serves to connect the sucalone serving as a spacing means;

cessive units when the same are placed upon the Fig. 9 is a perspective view of a further modi pipe so that all form a continuous whole. Also fication of my invention showing different spacby indenting at spaced intervals inward projecing mea s; 45 tions in the crimped end I find that such pro- Fig. 10 is a fragmentary longitudinal cross secjections form a. sufiicient resilient spacing means tion of the pipe covering shown in Fig. 9 applied from the pipe, although I find that the crimped to a pipe; and

end alone if elongated may serve as emcient spac- Fi 11 is n e d w Of F g- 10 h t e Paris mg means. The spaced projections allow fewer in position on a pipe. 50 points of contact and therefore lower heat losses In these drawings, a unit or section III of pipe from conduction. insulation covering or casing is formed in a gen- The sheet metal pipe covering will generally be erally U-shape. The pipe casing may be formed formed of sheet steel tin-plated or bright metal of any flexible resilient sheet metal with a bright plated, or covered with aluminum or other bright surface, for example sheet aluminum II, as in- 55 dicated in Figs. 1 and 2, or as illustrated in the cross section in Fig. 3 the pipe casing may be formed of sheet steel l2 coated as shown with aluminum foil' I 4 on both sides, but foil on both sides is not necessary. The aluminum foil may be retained in place by any suitable adhesive. I have found that sheet steel when dipped into glues of a phenol-resin type dissolved in a volatile solvent, and allowed to dry, retain the foil very well when the latter is applied to the sheet steel with heat and pressure.

Each unit ill of pipe covering preferably is formed in about three foot lengths so that the same may be easily shipped and handled; it will be noted that the U-shape shown in Fig. 2 will allow the nesting of these units so that the same occupy relatively little space in shipping.

The loss of heat by radiation isprevented by the bright metal surface of the pipe covering, the loss of heat by convection is prevented by the body of the covering itself, and the loss of heat by conduction is best prevented by spacing the pipe covering l0 away from a pipe l5 as clearly indicated in Fig. 5 by projections I6 which contact the pipe at widely separated points. The projections l6 preferably will be formed in a crimped end portion 18 of unit II and project inwardly of the covering to a greater extent than said crimped end portion II which will ordinarily be formed at one end of each unit. The crimped end portion 18 serves as a connective means to link the successive units ll one to another and projections 16 seperate or space said successive units H) from the pipes upon which the units are mounted. Also the crimped end portions l8 facilitate the easy overlapping of successive units l0 which latter will usually be separately mounted upon the pipe and connected by sliding any unit 10 along the pipe so that its crimped portion l8 enters the uncrimped end portion I8a of the adjacent unit. The crimped end portion it acts as an alignment means to center and connect successive units of the covering. Ordinarily, for good efliciency, the internal diameter of the pipe covering when in position should be approximately 1 inch greater than the external diameter of the pipe.

The projections l6 therefore are not strictly necessary and the crimping itself, if formed deep enough, can be used if desired to space the pipe covering from the pipe, as indicated in Fig. 8. One important feature of my invention is the provision of an efficient resilient spacing means integral with the pipe covering which contacts the pipe slightly, such spacing means being at an acute angle to the longitudinal axis of the pipe covering when the latter is in position. The acute angle of the spacing means allows its easy flexing when the casing is being positioned.

The U-shaped units at their longitudinal edges are provided with complementary and engageable hook shaped flanges 2|! and 22 respectively, which interlock and which when interlocked will maintain the U-shaped member in a generally tubular shape under tension, the resiliency of the flexible U-shaped member maintaining the same in such shape. If the covering H1 is foil mounted, these hook shaped flanges 20 and 22 tend to hold the foil firmly in place and so resist any peeling tendencies.

By virtue of the end portion l8 being crimped and at an acute angle to the pipe covering, the crimped portion can be flexed outwardly when mounting the pipe covering and when interlocking the hook shaped flanges 20 together. Resiliency of both the crimped end l8 and the spacing means l6 allows the firm positioning of my pipe covering and both preferably should be arranged so that they are compressed slightly out of their normal position by the tension of the covering Hi. When so arranged the compression forces of the spacing means will oppose the tension of the covering and the covering will be firmly positioned on the pipe by virtue of the opposite forces set up. Also the spacing means I must be sufliciently resilient and flexible since they normally will be bent outwardly beyond their normal position when upon the pipe during the operation of engaging the hook shaped flanges 2| and 22.

A section or unit ll of the pipe covering may be positioned on a pipe in a relatively few seconds and thereupon another section may be flexed into position adjacent thereto but not touching the same, which latter section is then slid along the pipe until its crimped end ll tightly fits into the uncrimped end |8a of the adjacent section as indicated in Fig. 4. By this means successive sections can be rapidly mounted in place upon a pipe and a large amount of pipe can be covered in a comparatively short time. The crimping allows the easy entry of the crimped end portion l8 into uncrimped end Ila so that the crimping serves both as an alignment means and a connective means. .If desired, the sections l0 can be slightly tapered so that the narrow ends will telescope for a short distance; actually as indicated in Fig. 4 the thin gage metal sections will ordinarily telescope slightly without such tapering.

If desired, for added insulation efliciency, it is possible to mount two successive coverings 24 and 26 one above the other respectively, as indicated in Figs. 6 and 7. It is obvious that pipe covering so mounted can be rapidly taken down without harm 'or loss, simply by disengaging the sections and unhooking the flanges.

A modified form of spacing and connective means which I have found efliciently blanks out of sheet metal is shown in Figs. 9 and 10. In this form the spacing means comprises tabs 2| arranged in spaced relationship at one end of a unit or section 30 of pipe covering and at an acute angle to the horizontal axis thereof, as indicated in Fig. 9. These tabs 28 ordinarily touch the pipe only tangentially and should be relatively narrow in width so that they will be springy and resilient; it is the width of the members and their acute angle to the pipe covering which gives them their flexibility and which allows the pipe covering to be easily mounted in place upon a pipe. These tabs 28 in addition to spacing the pipe sections 30 from a pipe, also facilitate connection of one section of pipe to another particularly by forming an entering and aligning means for one section of a pipe and the adjacent section. The sections 30 may be joined by sliding one section along the pipe to the next section. In the type of unit or section shown in Fig. 9 one end, namely the end which carries tabs 28, is formed of a slightly narrower diameter than the other end of such section; this allows a tight union between successive sections of the pipe covering.

It is to be understood that while the illustrated forms of the invention which I have described represent certain preferred embodiments, I do not wish to limit myself precisely to these details, since it is obvious the same may be considerably varied without departing from the spirit of the invention as defined and claimed in the appended claims.

What I claim is- 1. An all-metal covering for a pipe comprising a plurality of units each formed of flexible resilient sheet metal provided with a bright surface, each unit comprising a covering member normally assuming a U-shape but adapted to be flexed to a generally tubular shape, means adapted to retain the same tubular when the same is in a tubular shape, means for spacing said covering member away from a pipe, and means for connecting successive units of the pipe covering, said spacing and connective means being integral with said covering member.

2. A structure as defined in claim 1 wherein said connective means comprise a crimped end portion of said covering member and wherein said spacing means comprise a plurality of spaced in ward projections in said crimped end portion, said projections extending a greater distance inwardly of said covering member than said crimpmg.

3. A structure as defined in claim 1 in which said spacing means comprise flexible spring members adapted to contact with the pipe at relatively few points and formed at an angle to the longitudinal axis of said pipe covering when said pipe covering is in position.

4. A structure as defined in claim 1 in which said spacing means comprise flexible spring members adapted to contact with the pipe at relatively few points and formed at an angle to the longitudinal axis of said pipe covering when said pipe covering is in position, said spacing means being arranged so that when the pipe covering is in position the spacing means are bent under compressive forces and retain the covering in spaced relation with the pipe, the forces in' said flexed spacing means being opposed to the tension of the U-shaped member when the latter is flexed into tubular shape, whereby the covering tends to remain in fixed position.

5. An elongated all-metallic covering unit for a pipe comprising flexible and resilient sheet material having a bright surface formed in a generally U-shaped cross section adapted to be flexed into a generally circular cross section, means adapted to maintain said unit in said circular cross section, flexible spacing means adapted for spacing the unit from a pipe so that an air space is formed therebetween, said spacing means being integral with said unit and being angularly disposed with respect to the horizontal axis of said unit, and alignment and connective means adapted to connect successive pipe covering units, said alignment and connective means being an inwardly crimped end portion of said unit.

6. In a pipe covering of flexible resilient sheet metal provided with a bright surface normally assuming a cross section of U-shape but adapted to be flexed into a generally circular cross section, means integral therewith adapted to hold the covering in a generally circular cross section and a flexible indented end portion disposed at an acute angle to the horizontal axis of the covering adapted to space the covering from a pipe, said indented end portion being also adapted to serve as an alignment means to align successive units of the covering.

ROE R. BLACK. 

